Genuine OEM Volkswagen Vent Hose, part number 2Q0121447A. This hose serves as a crucial component in the cooling system, designed to allow air to escape from the system, thereby preventing excessive pressure buildup. Proper venting ensures the cooling system operates efficiently and prevents potential damage from over-pressurization. The hose is constructed from materials resistant to heat and coolant exposure. Genuine OEM parts guarantee the correct dimensions and material properties for reliable performance and system integrity.